How does this medication work? What will it do for me?

Timolol belongs to the class of medications called beta-blockers. It is used for the treatment of high blood pressure. It is also used to prevent angina (chest pain), and to reduce the risk of having another heart attack after a heart attack has happened. Timolol is also used for the prevention of migraine headaches but is not useful for treatment of a headache once it has started.

Timolol blocks the action of chemicals that increase the heart's workload. Beta-blockers such as timolol lower the heart rate, blood pressure, and force of heart contraction. It is not known how beta-blockers work to prevent migraine headaches.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Nu-Timolol is no longer being manufactured for sale in Canada. For brands that may still be available, search under timolol. This article is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.

How should I use this medication?

The recommended adult dose of timolol depends on your circumstances and the condition being treated.

The starting dose for treatment of high blood pressure is usually 5 mg to 10 mg taken 2 times a day. Timolol is often used along with other medications to treat high blood pressure. The dose of medication is gradually increased by your doctor until the dose that is most effective for you, with the fewest side effects, is found. The maximum daily dose of timolol is 60 mg per day.

When treating angina, the starting dose is 5 mg taken 2 to 3 times daily. It may be gradually increased by your doctor to between 15 mg and 45 mg daily.

The usual dose to prevent another heart attack after the first one is 10 mg taken 2 times daily. Your doctor may suggest you start with a lower dose and then gradually increase.

The dose used to prevent migraine headaches is usually 10 mg taken 2 times a day, but it may range from 10 mg per day to 30 mg per day.

Timolol may be taken with or without food. Do not stop taking this medication suddenly without speaking with your doctor first.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones given here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Stop taking the medication and seek immediate medical attention if any of the following occur:

signs of a heart attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)

signs of stroke (e.g., sudden or severe headache; sudden loss of coordination; vision changes; sudden slurring of speech; or unexplained weakness, numbness, or pain in the arm or leg)

symptoms of a severe allergic reaction, e.g.:

difficulty breathing

hives

swelling of the face or throat

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Angina: If you are taking timolol to treat angina, do not stop the medication suddenly. There have been reports of severe worsening of angina, and of heart attack or abnormal heart rhythms occurring for people with angina who have done this. If it is necessary to stop this medication, talk to your doctor about how to safely do so.

Breathing problems: Like other beta-adrenergic blockers, timolol can cause difficulty breathing for people who have asthma and certain other breathing problems. If you have breathing problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Diabetes: The signs of low blood sugar may not be as noticeable when taking timolol. People who have diabetes who take insulin or other medications that work by reducing the levels of sugar in the blood should monitor their blood sugar carefully while taking this medication.

Kidney function: The kidneys are partially responsible for removing this medication from your body. Kidney disease or reduced kidney function may cause this medication to build up in the body, causing side effects. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Myasthenia gravis: Myasthenia gravis is a condition that causes specific muscle weakness. Timolol can cause increase the symptoms of this illness. If you have with myasthenia gravis, should discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Thyroid disease: Timolol may hide the symptoms caused by an overproduction of thyroid hormone. If you have a history of thyroid problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Surgery: If you are going to have surgery, make sure you tell everyone involved in your care that you are taking this medication. It may be necessary to gradually reduce the dose of timolol, or stop the medication temporarily.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking timolol, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

stop taking one of the medications,

change one of the medications to another,

change how you are taking one or both of the medications, or

leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.